Tractor-truck constructio



P.E\.\H0LT. TRAUM TRUCK coNsTRucnoN. APPucA-rfqw-IH-LED mp1s. 1919. 1,394,996. Pgtented Oct. 25, 192] 2 SHEETS-SHEET l.

, mvENTQR ya@ mwa BY PfE. HOL-f.

TRACTOR TRUCK CONSTRUCTION.

APPLlcATloN min APRI 1s. 1919.

UNTED STATESPATNT OFFICE.

il'xl E. IGLT, 0F STGTON, GALEFOR-NEA, LSSIGNOR TO THE '.URlNG @GMP-ANY, 0F STOCKTDN, CALIFGRNIAL. CIRPORATION O HOLT MANUFAC- F CALIFORNIA.

TRACTOR-TRUCK COi'STRUCTIG" lggggl. Specification of ietters latent. Patented Oct. 25, 192L Application iled April 16, E919. ilerial lo. 2'0,43l.

To allie/wm it may concern: Y frame l0 `Se it known that l, PLrNY E. H oifr, a inf;- .provides a suitable support for a @eigen of the United States, residing at rear aide le. 'his general construction as Stockton, in the county of San Joaquin and Well as certain details of the truck stzzuc- State or California, have invented new and ture, have been more fully disclosed in a useful linprovernfnuts in Tractor- Truclr lco-pending application entitled Chain Constructions, of which the following is a track tractor, ld May 25, 1918, and bearspecufication. ing the Serial No. 236,523. The axle ,14 is rvillus invention relates to tractors ci the iitted with chain tracky supports l5 yelilaying track type and has for its object which anv articulate track 16 is led. This 84.5 o provide a self-laying track mechanism traclr also embraces idler wheels 17, dis o ltractors of this type, which will antonear the forward end of the main frame and". i tieally adjust itself when obstructions carried in bearings 18 mounted lupon front ck sections Aa occur between the track and the wheels truclr sect-ions 19. The front tru as is here shown, is a single casti lo around which it moves or when ineualiare fitted with a luralit of loa s l I l P y uPPOI .ies are encountered in the surface traveled ing rollers 20, adapted to pass alongthe over, and will thus prevent excessive bindlowerl'uri of tracl: and are rotatably 'secured ing yor tightening oi" the track under these beneath these sections. Near the `forward mums/M6832 end of the truck sections 19 is disposed an z resent invention this is accomequalizer bar 2l, which passes across and 75 p ed by employing the usual main traine beneath the main frame and is centrally with an endl-ees flexible traclz, a drive pivoted thereto, the outer ends of said bar sprocket for said track journaled on the being pivoted to the truck units at the 0pinain frame and carrying one end of the poSite sides of the main frame, The rear :25 traclr, and an idler journaled on a roller end of the forward truck units 19 are con- 30 truclr i''ranie, carrying the other end ot the nccted with rear truck units 22 by means of track, the roller truck traine being provided hinge pins 23. These pins extend horizonwith rollers engaging the ground run oi the tally through hinge castings 24 and 25, fastrael-. Suitable means are provided to suptened A,upon the rear and front truck sections art the main traine. on the roller truck: respectively.-

ineans of this connection, me, and means are also provided to trans the complementary sections of each truck horizontal movement of the main frame unit may move vertically in relation t0 each ifo the roller truck trarne in such a manner other. ihe inain frame is formed with an that l ted ,horizontal vmovement of' the Outrigger casting 26, which extends from- /uck traine in relation t@ the niaiu each side of the frame and is designed with roller frein .v'illjbe permitted when excessive tenseat-s to receive the upper vends of load supsicn in the trad.; occurs., porting springs 27 and 28. These springs rlhe track drive sprocket and idler a rest upon a top plate 29, forming a part of sprocket are thus permitted to approach the rear truck structure and which also carry zo each other, thereby producing sufficient a pair of lupwardly extending lugs 30. .95 slaelt in the track to prevent undue strains These lugs are spaced in relation to each 'when obstructions iind their way between Other and extend longitudinally of the truck track andthe wheels about which it sections 22, thus accommodating the lower rnoves or when inequalities are encountered ends of a li, i member 31. This link hangs 5 in the surface traveled over. downwardly from its pivot pin 32 upon the 100 Referring to the drawings, Figure l is a Outrigger casing and is formed with an view in side elevation, illustrating a truck elongated slot` through which a truck pin 33 unit and the niain frame supported thereby. extends. The width of the link is such that Fig. 2 is a view in plan, illustrating the the truck sections 22 will be held against nia-in frame and the truclr units'at the op transverse horizontaltwistingmovenient. At 105 posits sides thereof. l the saine time the slot will allow the truck Referring more particularly to the draw sections to move vertically, as desired and ings, l0 indicates a main frame upon which in a freely floating manner. The rear trucks is mounted a Suitable power plant. 1l and a are, of course, tted with load supporting transmission mechanism l The main rollers 20, as previously described, and rest ber 41 carr ino' a stem 42 which' is free to slide Within the central opening of the meni-l ber 39. This second shackle is vpivoted to a casting 43, 'carriedby the front truck sections 519 and is directly attached to a lug ,44 by means of a shackle pin45. A n examination of the drawing will disclose the tact vthat the two shackles may move toward or away from each other as .the stem 42 telescopes within, the tubular member 39, this action being dependent upon the expansion and contraction ofthe spring 40 which is interpos'ed between the shoulders of the shackles 37 and 41. It will also be noted that the cushion structure comprising the shackles andtheir spring is pivotally connected across the hinge connection between the truck sections, thus acting to yieldably resist the upper movement of the opposite ends ofthe truck sections 19 and 22 and a't the same time allowingr the trucks to collapse in theevent that the track becomes excessively tight, due to any condition.

In reviewing the action, made possible.Y by the structure embodied in the present invention, it will be noted that the front and rear truck sections may move vertically in unison; thatthe frontI section may move vertically as it pivots upon a 4hinge pin 23 and as equalizedby the cross member 21. Furthermore, the rear section may pivot upon the hinge pin 23 as permitted by' the compression of thes rings 27 and 28. At

the sam'e time a col apsing vaction may be produced' between? the two truck sections, due to the compression of the spring 40, thus providing a truckthich will constantly maintain the track in. a proper tensioned condition and at the same time will permit the truck to collapse to accommodate the .track when excessive strains are produced.'

vHavingr thus described my invention, what claim and desire to secure by Letters Pat ent is- 1.- In a chain track tractor, a main frame, anv endless flexible track having one end supported on a track drivi1ig,sprocket journaled on the main frame and the other end supported on an idler journaled on a roller truck frame, rollers on the truck `trame, engagingr he ground nm ofthe track, means to support the'main frame on the roller truck Lacasse frame, and resilient means to transmit horizgontal movementpt the main frame 'to 'the roller truck frame.

2. In a chain track tractor, a main trarne,

an endless exible track having one end. snphorizontal movement of the roller truck trame in relation tothe main trame when excessivetension is applied to the track.

3. Ina chain track tractor, a main trarne, an endless exible track having; one end sup ported on a track driving sprocket journaled on the main frame and the other end supported onl an idler journaled on a roller truck frame, roliers on the truck frame engaging the ground run of the track, means to support the main frame ontne roller truck trame, and means interposed between the mainframe and the roller truck trame in a manner to permit the idler to approach the track drive sprocket and produce slack in the track.

4. ln a chain track tractor, a main frame, an endless flexible track having one end supj ported on a track driving,r sprocket journaled on the main trame and the other end supported on an idler journaled on a roller truck frame, rollers on the 'truck 'frame en earring the `round run ofthe track, means to support the main frame on the roller truck trame, and means interposed between the main frame and the roller truck frame in a manner to permit the idler to approach the track driv'e sprocket andprod'ucefslack in the track. said means comprising a spring thrust link havingl one end secured to the main trame and the other secured to the roller truck `trame.

5. ln a chain track tractor, a main traine, an endless flexible track having one end supported by a track drive sprocket journaled on the main trame and the other supported on an idler journaled on an articulated roller truck trame, rollers for the truck traine engaging the ground run of the track, resilient' means to support the main trame upon the roller truck frame. and inca'ns interposed between the main trame and the roller truck trame in a manner to permit the idler to approach the track drive sprocket and produce lslack in the track. said means comprisiuggl a spring thrust link havingA one encfy secured to the main frame and the other secured to the forward section oit-the roller truck trame.

6. ln a tractor, a driving sprocket rotatably fired to the ,tractor main frame, a pair of truck sections hinged together and disposed in Walinexnent withy said driving sprocket, an idler wheel carried by the forward section, a chain tread track embracing said sprocket and idler Wheels and the truck sections, means for yieldably suspending the main frame from said front and rear truck sections and resilient means adapted to yieldingly resist a hinging action between the two sectlons.

7. In a tractor construction, a main frame, a drivin axle carried by the rear end thereof, driV ng sprockets upon the opposite ends of said axle, afreely movable truck section, means for yieldably supporting the rear end of the main frame from said truck section, a freely movable truck section pivoted to said first named section, porting the forward ,and of from said section, bythe front section,

the maln frame anjidler wheel earned front truck section normally resisting front and re other.

In testimony 'my hand in the witnesses.

Witnesses: W. W

and the main frame for a hinged action ofthe ar sections in relation to 'each whereof I have hereunto set presence of two -subscribing PLINY E. HoL'r.

. HEALEY, EWING.

a chain track. embracin means lfor sup- 

